This is the simplest way to parallel lm3886 chip. There is no servo, they are not needed.

Use one half of a dual op amp per channel. The value for the resistors is up to you, I use 4.2K.

Two pins of the trimmer are connected together and one pin is connected to ground.

Before connecting the outputs check, each chips dc. Turn the trimmers until dc is zero out or as close to zero as you can get it (usually around .1 to .3 mv). Now connect the outputs together

Thanks a lot for your suggestion. But if the dc is made zero by this procedure, I do not know whether it will have some negative effect on the sound quality. I am curious because I have not seen this method before in any of the application notes of NS. There they always suggest to use a dc-servo when paralleling.
In any case I will try it also.

Spent a lot of time for this revision of the pcb. Please give me your opinion. Tried to follow the application notes and some suggestions I received here. The pcb looks very complicated, but I hope it is a good design.

there are Zobels added in the pcb which are not there in the circuit diagram. also as I do not have enough low voltage 0.1uF, I had to use those fat ones (panasonic 0.1uF630v) that made the board a bit big. AD8620 is placed on the bottom of the board.

regarding making the pcb I contacted some company here in mumbai. they need the order for at least 10 pcbs. I need only 2. would anybody like to join me for the pcb, if interested in the circuit? I am not trying to make a group buy, need to give away the remaining 8 and only within India. i do not know any other company who will make only 2 for me. if anybody has some information please share.....